Three-dimensional animations often appear in the movies or TV programs nowadays, and three-dimensional animation authoring tools are used for authoring such three-dimensional animations, but the conventional three-dimensional animation authoring tools are too complicated and difficult to use so that only persons of professional skill can use such tools.
Recently, due to the development of Internet and multimedia, general users who want to actively author and use three-dimensional animations rather than passively watch them are increasing.
Thus, non-professional tools to enable general users, including children and beginners, to author their own three-dimensional animations have been developed, and such non-professional tools create an animation of an object according to routes and motions simultaneously drawn on a screen by a user. However, accurate input of both the routes and motions is impossible and the motions that can be inputted are highly limited since both the routes and motions are simultaneously inputted.
Therefore, an animation authoring tool which enables non-professional users to easily author three-dimensional animations and to accurately input routes and motions of an object is increasingly needed.